And in 2017, the tech giants sought to project their power even further. Facebook built its lead on Snapchat by gradually swiping away the best part of the upstart's app. Apple released a new iPhone designed to conquer augmented reality, the next frontier. Microsoft took swipes at Amazon, Apple, and even startups like Slack. Google doubled down on building its own hardware.

To my mind, though, the single biggest and most aggressive move this year was by Amazon, with its $13.7 billion acquisition of Whole Foods. It wasn't a tech deal, in the traditional sense. But it caused ripples that go beyond just groceries — ripples that are slowly turning the entire US economy into a case of Amazon versus everybody else.

It's a mark of how seriously corporate America now takes Amazon: When Amazon acts, the world reacts. And as we enter 2018, it's becoming clear that either you're against Amazon or, eventually, you might just become part of Amazon.